Field of the Invention
The present invention relates to a positioning processing apparatus, a positioning processing method, and a recording medium.
Related Art
Thus far, a positioning processing apparatus has been known that performs positioning using GPS (Global Positioning System).
When performing positioning using GPS, although it is desired to distinguish a position within a short time of period, it requires a certain period of time to receive from GPS satellites information relating to the orbits of the GPS satellites for positioning (hereinafter, referred to as “Ephemeris”).
For this reason, it is difficult to shorten the period of time required for distinguishing a position to a period of time less than a certain period of time upon adopting the method of receiving Ephemeris from the GPS satellites.
In order to address this problem, for example, Japanese Unexamined Patent Application, Publication No. 2011-141144 describes, as a method for distinguishing a position more promptly, a method adopting predicted Ephemeris that is acquired in advance prior to positioning, which is different from Ephemeris that is received from the GPS satellites upon positioning.
For the predicted Ephemeris, predicted Ephemeris accumulated in an assist server (hereinafter, referred to as “download-type predicted Ephemeris”) and predicted Ephemeris calculated at a GPS receiver based on the Ephemeris received from a GPS satellite (hereinafter, referred to as “self-predicted Ephemeris”) have been known.
It is possible to perform positioning promptly compared to the case of receiving Ephemeris from a GPS satellite using a predicted Ephemeris.
However, the download-type predicted Ephemeris can receive a vast amount of predicted Ephemeris (for example, an amount for a month) via the network while it consumes a greater amount of energy for accessing the network compared to the case of receiving Ephemeris from the GPS satellite. Furthermore, the self-predicted Ephemeris has a shorter validated period of time during which predicted Ephemeris can be calculated (for example, three days) compared to that of the download-type predicted Ephemeris.
Therefore, a period of time that can realize positioning promptly using predicted Ephemeris is not sufficient. As such, it has been difficult with the conventional technologies to reduce power consumption appropriately and perform positioning promptly.